CN102676857A - Preparation method of high-density B4C-Al homogeneous neutron absorber material - Google Patents
Preparation method of high-density B4C-Al homogeneous neutron absorber material Download PDFInfo
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- CN102676857A CN102676857A CN2012101554335A CN201210155433A CN102676857A CN 102676857 A CN102676857 A CN 102676857A CN 2012101554335 A CN2012101554335 A CN 2012101554335A CN 201210155433 A CN201210155433 A CN 201210155433A CN 102676857 A CN102676857 A CN 102676857A
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Abstract
The invention discloses a preparation method of a high-density B4C-Al homogeneous neutron absorber material. The method comprises the following steps of: uniformly mixing B4C and Al alloy powder according to a preset chemical proportion; putting into an aluminium alloy box with an aluminium alloy frame; vacuum sintering; hot rolling; rolling through inverting at 90 degrees when the density of billets reaches 70 percent-95 percent TD; removing an aluminium alloy jacket on outer layers of the billets; rolling to be preset size; and annealing to obtain the neutron absorber material with the density being above 98 percent. The preparation method has a simple process and low requirement on equipment. The prepared B4C-Al neutron absorber material is a homogeneous material, has high density and stable use performances, and can be used as the neutron absorber material for critical safety control in spent fuel storage facilities.
Description
Technical field
The invention belongs to a kind of preparation method of matrix material, be specifically related to pine dress powder framework peeling rolling and prepare high density homogeneous B
4The preparation method of C-Al neutron absorbing material.
Background technology
The Boral metal matrix composite sheet is to be composited in alloy matrix aluminum by the norbide even dispersion, and wherein norbide is the dispersion-strengthened phase, and duraluminum is the matrix phase.This material contains the good B element of neutron absorptive character, can be used as the neutron absorbing material.Its remarkable advantage is high, the long service life of corrosion-resistant, anti-irradiation, boron content, can improve the economy and the security of spent fuel storing.
B
4C-Al neutron absorbing material, external preparation method has several different methods such as fusion casting, powder metallurgy, and the whole bag of tricks has the characteristics of himself, and the reaction of fusion casting material interface is serious, and the powder metallurgic method preparation technique process is complicated.And the method that the powder metallurgy press working combines can be improved the distributing homogeneity of norbide greatly.It like application number 201010602530.5 Chinese patent; " a kind of preparation method of high-density neutron absorber plate " described, this method be mixed powder is contained in the duraluminum box rolling, in the operation of rolling; Mixed powder is closely knit gradually and reach metallurgical binding with aluminum alloy casing; Form a kind of material of metallurgical binding everywhere of Layer cake dry type, the operation of the duraluminum involucrum not being removed in the operation of rolling is so can not prepare B
4The homogeneous material that the C even dispersion forms in alloy matrix aluminum.
Summary of the invention
The object of the present invention is to provide the simple high-density B of a kind of preparation technology
4The preparation method of C-Al homogeneous neutron absorbing material.
Technical scheme of the present invention is following:
A kind of high-density B
4The preparation method of C-Al homogeneous neutron absorbing material, step is following:
The step 1 batch mixing: with mean particle size is that Al alloy powder and the mean particle size of 35 ~ 60 μ m is the B of 10 ~ 60 μ m
4The C powder is the ratio of 90-35%: 10-65% by mass percentage, and two material are mixed in mixer;
Step 2 charging:, be encapsulated in the duraluminum box of aluminum alloy frame with the powder that mixes;
Step 3 vacuum stripping sintering: the duraluminum box after will encapsulating is inserted and is carried out the vacuum stripping sintering in the vacuum oven, makes the vacuum tightness of vacuum oven remain on 10
-2~ 10
-3Pa, the agglomerating furnace temperature is 350 ~ 540 ℃, sintering time is 6 ~ 20h;
Step 4 hot rolling: the duraluminum box behind the sintering is carried out the hot rolling of multi-pass under 350 ℃-540 ℃; Draught be every time 10 ~ 15%; When the density of blank in the box reaches 70%-95% TD, commutate 90 ° rolling and remove the duraluminum involucrum of blank, carry out the multiple tracks hot rolling again; Draught is 30 ~ 40%, up to the sheet material that blank is rolled to pre-determined thickness;
Step 5 anneal: sheet material is carried out anneal, process density and be 98.5 ~ 99.2% neutron absorbing material.
In the said step 4; The 90 ° of rolling process sequences with removal duraluminum involucrum that commutate can freely be selected; As long as blank density reaches 70 ~ 95%TD; Two technologies can be carried out when blank is in different densities, also can when blank is in identical density, carry out, and can ensure effectively that 15 meters long sheet material pressed density is evenly solid not ftracture.
Effect of the present invention is: compared with prior art, preparation method of the present invention does not need large-scale press and extrusion machine, and technology is simple relatively, and equipment requirements is not high, the B of preparation
4C-Al neutron absorbing material is a homogeneous material, has the density height, and use properties is stable, and density of material reaches more than 98%, can be used as the neutron absorbing material of controlling as criticality safety in the irradiated fuel store facility, realizes the intensive storage of spent fuel.
Embodiment
Preparing method of the present invention is: according to the predetermined chemical proportioning with B
4After C and Al powdered alloy mix, encapsulate after inserting duraluminum box, carry out the vacuum stripping sintering with aluminum alloy frame; To remove moisture in the mixed powder, make the certain sintering of generation between powder particle bonding, help follow-up combination; And then the box behind the sintering carried out hot rolling, when the density of blank reached 70%-95%TD, it was rolling to ensure density homogeneous material sturdy construction to carry out 90 ° of switching-overs; And adopt mechanical means to remove the outer field duraluminum involucrum of blank, carry out the hot rolling of multi-pass again, make the fine and close metallurgical binding of step material after; Be rolled to the sheet material of pre-determined thickness, panel density is reached more than the 98%TD.Wherein, the 90 ° of rolling process sequences with the removal involucrum that commutate can freely be selected, and both can carry out when blank is in different density, also can be in identical density at material and carry out, as long as blank density reaches 70 ~ 95%TD.
Concrete preparation process is following:
Step 1 batch mixing: with massfraction 10 ~ 65%, mean particle size B at 10 ~ 60 μ m
4The C powder, the Al matrix powder of massfraction 35 ~ 90%, mean particle size 35 ~ 60 μ m mixes in mixer;
Step 2 is feeded: encapsulate after mixed powder is inserted the duraluminum box with aluminum alloy frame;
Step 3 vacuum stripping sintering: the duraluminum box of powder mix blank is arranged in inciting somebody to action, place vacuum oven to carry out the vacuum stripping sintering, keeping the vacuum tightness of vacuum oven is 10
-2~ 10
-3Pa, sintering temperature is 350 ~ 540 ℃, sintering time is 6 ~ 20 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out the hot rolling of certain passage under 350 ℃-540 ℃; Draught be every time 10 ~ 15%, when the density of blank is 70%-95% TD, commutate 90 ° rolling; And the outer field duraluminum involucrum of removal blank; Carry out the multi-pass hot rolling again, draught is 30 ~ 40%, is rolled to the sheet material of pre-determined thickness;
Step 5 anneal: the sheet material after the hot rolling peeling is carried out anneal, process the neutron absorbing material of density 98.5 ~ 99.2%.
Below in conjunction with embodiment the present invention is further described:
Embodiment 1
Step 1 batch mixing: with the B of massfraction 10%, mean particle size 10 μ m
4The C powder, massfraction 90%, the Al matrix powder of mean particle size 40 μ m mixes in mixer;
Step 2 charging: powder mix inserted in the duraluminum box with aluminum alloy frame encapsulate;
Step 3 vacuum stripping sintering: will be packaged with the duraluminum box of powder mix blank, being put into vacuum tightness is 10
-3Carry out the vacuum stripping sintering in the vacuum oven of Pa; 510 ℃ of sintering temperatures, sintering time are 10 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out continuous multiple tracks hot rolling under 350 ℃; Draught be every time 10%, when the density of blank is 70% TD, 90 ° rolling of commutating; And the outer field duraluminum involucrum of removal blank; Carry out the multi-pass hot rolling again, draught is 40%, is rolled to the sheet material of thickness 2.7mm;
Step 5 anneal: the sheet material after the hot rolling is carried out anneal, process density and be 98.5% neutron absorbing material.
The tensile mechanical properties of sheet material is as shown in table 1 under above-mentioned preparation condition:
Table 1 Al+10%B
4The C material mechanical performance
| Sample | Ys RP0.2/MPa | Tension is strong RM/MPa | Unit elongation A/ % |
| Al+10%B 4C | 120 | 158 | 1.2 |
Embodiment 2
Step 1 batch mixing: with the B of massfraction 26%, mean particle size 35 μ m
4C powder, massfraction 74%, mean particle size are that the Al matrix powder of 60 μ m mixes in mixer;
Step 2 charging: with embodiment 1;
Step 3 vacuum stripping sintering: will be packaged with the duraluminum box of powder mix blank, being put into vacuum tightness is 10
-3Carry out the vacuum stripping sintering in the vacuum oven of Pa; 540 ℃ of sintering temperatures, sintering time are 6 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out continuous multiple tracks hot rolling under 450 ℃; Draught be every time 10%, when the density of blank is 85% TD, 90 ° rolling of commutating; And the outer field duraluminum involucrum of removal blank; Carry out the multi-pass hot rolling again, draught is 35%, is rolled to the sheet material of thickness 2.5mm;
Step 5 anneal: the sheet material after the hot rolling peeling is carried out anneal, process the neutron absorbing material of density 98.5%.
The tensile mechanical properties of sheet material is as shown in table 2 under above-mentioned preparation condition:
Table 2 Al+10%B
4The C material mechanical performance
| Sample | Ys RP0.2/MPa | Tension is strong RM/MPa | Unit elongation A/ % |
| Al+26%B 4C | 126 | 159 | 2.3 |
Embodiment 3
Step 1 batch mixing: with the B of massfraction 35%, mean particle size 25 μ m
4The C powder, the Al matrix powder of massfraction 65%, mean particle size 45 μ m mixes in mixer;
Step 2 charging: with embodiment 1;
Step 3 vacuum stripping sintering: will be packaged with the duraluminum box of powder mix blank, being put into vacuum tightness is 10
-3Carry out the vacuum stripping sintering in the vacuum oven of Pa; 480 ℃ of sintering temperatures, sintering time are 15 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out continuous multiple tracks hot rolling under 540 ℃, draught be every time 10%, when the density of blank is 90% TD; Remove the outer field duraluminum involucrum of blank; When the density of blank was 95% TD, 90 ° rolling of commutating carried out the multi-pass hot rolling again; Draught is 30%, is rolled to the sheet material of thickness 2.0mm;
Step 5 anneal: hot rolled sheet material is carried out anneal, process density and be 98.8% neutron absorbing material.
The tensile mechanical properties of sheet material is as shown in table 3 under above-mentioned preparation condition:
Table 3 Al+35%B
4The C material mechanical performance
| Sample | Ys RP0.2/MPa | Tension is strong RM/MPa | Unit elongation A/ % |
| Al+35%B 4C | 145 | 168 | 2.5 |
Embodiment 4
Step 1 batch mixing: with the B of massfraction 50%, mean particle size 60 μ m
4The C powder, the Al matrix powder of massfraction 50%, mean particle size 60 μ m mixes in mixer;
Step 2 charging: with embodiment 1;
Step 3 vacuum stripping sintering: will be packaged with the duraluminum box of powder mix blank, being put into vacuum tightness is 10
-3Carry out the vacuum stripping sintering in the vacuum oven of Pa; 350 ℃ of sintering temperatures, sintering time are 20 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out continuous multiple tracks hot rolling under 480 ℃; Draught be every time 15%, when the density of blank is 95% TD, 90 ° rolling of commutating; And the outer field duraluminum involucrum of removal blank; Carry out the multi-pass hot rolling again, draught is 30%, is rolled to the sheet material of thickness 2.0mm;
Step 5 anneal: the sheet material after the hot rolling is carried out anneal, process density and be 99.2% neutron absorbing material.
The tensile mechanical properties of sheet material is as shown in table 4 under above-mentioned preparation condition:
Table 4 Al+50%B
4The C material mechanical performance
| Sample | Ys RP0.2/MPa | Tension is strong RM/MPa | Unit elongation A/ % |
| Al+50%B 4C | 128 | 169 | 1.03 |
Embodiment 5
Step 1 batch mixing: with the B of massfraction 65%, mean particle size 60 μ m
4The C powder, the Al matrix powder of massfraction 35%, mean particle size 35 μ m mixes in mixer;
Step 2 charging: with embodiment 1;
Step 3 vacuum stripping sintering: will be packaged with the duraluminum box of powder mix blank, being put into vacuum tightness is 10
-2Carry out the vacuum stripping sintering in the vacuum oven of Pa; 350 ℃ of sintering temperatures, sintering time are 20 hours;
Step 4 hot rolling peeling: the duraluminum box behind the sintering is carried out continuous multiple tracks hot rolling under 510 ℃, draught be every time 10%, when the density of blank is 83% TD; Commutate 90 ° rolling; When the density of blank is 90% TD, remove the outer field duraluminum involucrum of blank, carry out the multi-pass hot rolling again; Draught is 30%, is rolled to the sheet material of thickness 2.7mm;
Step 5 anneal: the sheet material after the hot rolling is carried out anneal, process density and be 99.1% neutron absorbing material.
The tensile mechanical properties of sheet material is as shown in table 5 under above-mentioned preparation condition:
Table 5 Al+65%B
4The C material mechanical performance
| Sample | Ys RP0.2/MPa | Tension is strong RM/MPa | Unit elongation A/ % |
| Al+65%B 4C | 138 | 178 | 0.78 |
Claims (2)
1. high-density B
4The preparation method of C-Al homogeneous neutron absorbing material, step is following:
The step 1 batch mixing: with mean particle size is that Al alloy powder and the mean particle size of 35 ~ 60 μ m is the B of 10 ~ 60 μ m
4The C powder is the ratio of 90-35%: 10-65% by mass percentage, and two material are mixed in mixer;
Step 2 charging:, be encapsulated in the duraluminum box of aluminum alloy frame with the powder that mixes;
Step 3 vacuum stripping sintering: the duraluminum box after will encapsulating is inserted and is carried out the vacuum stripping sintering in the vacuum oven, makes the vacuum tightness of vacuum oven remain on 10
-2~ 10
-3Pa, the agglomerating furnace temperature is 350 ℃ ~ 540 ℃, sintering time is 6 ~ 20 hours;
Step 4 hot rolling: the duraluminum box behind the sintering is carried out the hot rolling of multi-pass under 350 ℃-540 ℃; Draught be every time 10 ~ 15%; When the density of blank in the box reaches 70%-95% TD, 90 ° of rolling and outer field duraluminum involucrums of removal blank that commutate, and then carry out the multiple tracks hot rolling; Draught is 30 ~ 40%, up to the sheet material that blank is rolled to pre-determined thickness;
Step 5 anneal: hot rolled sheet material is carried out anneal, process density and be 98.5 ~ 99.2% neutron absorbing material.
2. according to the described high-density B of claim 1
4The preparation method of C-Al homogeneous neutron absorbing material; It is characterized in that: in the said step 4; As long as blank density reaches 70 ~ 95%TD; The 90 ° of rolling orders with removal duraluminum involucrum technology that commutate can freely be selected, and two kinds of technologies can be carried out respectively when blank is in different densities, perhaps when blank is in same density, carry out simultaneously.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103614584A (en) * | 2013-11-07 | 2014-03-05 | 海龙核材科技（江苏）有限公司 | Preparation method of aluminium matrix composite with high B4C content |
| CN105499583A (en) * | 2015-12-16 | 2016-04-20 | 北京有色金属研究总院 | Preparation method for B4C/Al composite material boards |
| CN106735184A (en) * | 2016-11-30 | 2017-05-31 | 中国科学院金属研究所 | A kind of B high4The high efficiency preparation method of C content aluminium base neutron absorber material sheet material |
| CN107164755A (en) * | 2017-05-18 | 2017-09-15 | 江苏广川线缆股份有限公司 | The spraying method of neutron absorption composite material on a kind of stainless steel substrate |
| CN109825743A (en) * | 2019-03-20 | 2019-05-31 | 中国工程物理研究院材料研究所 | A kind of application method of structure-function integration neutron absorber material |
| CN110153187A (en) * | 2017-12-06 | 2019-08-23 | 安徽应流久源核能新材料科技有限公司 | A kind of milling method of aluminum-based boron carbide composite shielding material |
| CN112752624A (en) * | 2018-05-08 | 2021-05-04 | 万腾荣公司 | Method for producing a metal matrix composite strip product |
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| CN102094132A (en) * | 2010-12-28 | 2011-06-15 | 中国工程物理研究院核物理与化学研究所 | Method for preparing B4C-Al composite material |
| CN102110484A (en) * | 2009-12-25 | 2011-06-29 | 中国核动力研究设计院 | Method for preparing B4C-Al neutron-absorbing plate for spent fuel storage and transportation |
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Patent Citations (2)
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| CN102110484A (en) * | 2009-12-25 | 2011-06-29 | 中国核动力研究设计院 | Method for preparing B4C-Al neutron-absorbing plate for spent fuel storage and transportation |
| CN102094132A (en) * | 2010-12-28 | 2011-06-15 | 中国工程物理研究院核物理与化学研究所 | Method for preparing B4C-Al composite material |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103614584A (en) * | 2013-11-07 | 2014-03-05 | 海龙核材科技（江苏）有限公司 | Preparation method of aluminium matrix composite with high B4C content |
| CN105499583A (en) * | 2015-12-16 | 2016-04-20 | 北京有色金属研究总院 | Preparation method for B4C/Al composite material boards |
| CN106735184A (en) * | 2016-11-30 | 2017-05-31 | 中国科学院金属研究所 | A kind of B high4The high efficiency preparation method of C content aluminium base neutron absorber material sheet material |
| CN106735184B (en) * | 2016-11-30 | 2019-08-09 | 中国科学院金属研究所 | A kind of high B4The high efficiency preparation method of C content aluminium base neutron absorber material plate |
| CN107164755A (en) * | 2017-05-18 | 2017-09-15 | 江苏广川线缆股份有限公司 | The spraying method of neutron absorption composite material on a kind of stainless steel substrate |
| CN107164755B (en) * | 2017-05-18 | 2019-04-12 | 江苏广川线缆股份有限公司 | The spraying method of neutron absorption composite material on a kind of stainless steel substrate |
| CN110153187A (en) * | 2017-12-06 | 2019-08-23 | 安徽应流久源核能新材料科技有限公司 | A kind of milling method of aluminum-based boron carbide composite shielding material |
| CN112752624A (en) * | 2018-05-08 | 2021-05-04 | 万腾荣公司 | Method for producing a metal matrix composite strip product |
| CN109825743A (en) * | 2019-03-20 | 2019-05-31 | 中国工程物理研究院材料研究所 | A kind of application method of structure-function integration neutron absorber material |
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Application publication date: 20120919 Assignee: JIANGSU ENTC NUCLEAR TECHNOLOGY JOINT STOCK CO., LTD. Assignor: Nuclear Power Institute of China Contract record no.: 2015320000074 Denomination of invention: Method for preparing high-density B4C-A1 homogeneous neutron absorbing material Granted publication date: 20141210 License type: Exclusive License Record date: 20150320 |
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Inventor after: Liu Xiaozhen Inventor after: Liu Yunming Inventor after: Sun Changlong Inventor after: Li Gang Inventor after: Wang Meiling Inventor after: Wu Songling Inventor after: Zou Congpei Inventor after: Yi Wei Inventor before: Liu Xiaozhen Inventor before: Liu Yunming Inventor before: Sun Changlong |